KR20180031464A - Equipment for wet type carbon dioxide capturing - Google Patents

Abstract

Disclosed is wet type carbon dioxide capturing equipment including: a CO_2 absorbing column which makes CO_2 included in exhaust gas react with an absorbent; a CO_2 stripping column which separates CO_2 from rich solution absorbing CO_2 in the CO_2 absorbing column; a reheater which supplies thermal energy to the CO_2 stripping column so that CO_2 is separated from the rich solution in the CO_2 stripping column; a first heat exchanger which heats the rich solution by exchanging heat of the rich solution, absorbing CO_2 from the CO_2 absorbing column, and lean solution from which CO_2 is separated from the CO_2 stripping column; a mechanical vapor recompressor (MVR) which compresses CO_2 gas separated from the CO_2 stripping column; and a second heat exchanger which separates a part of CO_2 from the rich solution by heating the rich solution by exchanging heat of the rich solution, coming through the first heat exchanger, and CO_2 gas compressed in the MVR. CO_2 is separated from the rich solution, where CO_2 could not be separated in the second heat exchanger, by making the rich solution flow to the CO_2 stripping column. The present invention can save energy consumed to separate CO_2 from an absorbent in the CO_2 stripping column.

Description

[0001] The present invention relates to a wet type carbon dioxide capturing apparatus,

The present invention relates to a wet carbon dioxide capture equipment, and more particularly, to a wet carbon dioxide capture equipment having a configuration capable of reducing energy required for separating carbon dioxide from an absorbent.

In recent years, as the severity of global warming has become recognized, countries around the world have been struggling to prepare measures against greenhouse gases. One of the biggest causes of global warming is carbon dioxide (CO ₂ ). Accordingly, studies have been actively made on techniques for efficiently capturing carbon dioxide, which is the most important among greenhouse gases, to reduce carbon dioxide in the exhaust gas.

Although there are various technologies for capturing such carbon dioxide, the absorption method is evaluated to be more economical and easier to apply the process than other technologies. Chemical absorption among absorption method has a high CO ₂ removal efficiency benefits because it uses the selective separation of the CO ₂ in the exhaust gas of a chemical reaction.

CCS (Carbon Capture & Storage) refers to technologies related to capture, compression, transport, and storage of carbon dioxide. Of these, CCS is a technology for separating carbon dioxide in the exhaust gas emitted from a thermal power plant by a chemical absorption process. The process has been properly evaluated as commercialization technology.

In general, a liquid amine compound or liquid ammonia absorbs carbon dioxide, so that it can be applied to a process of removing a sulfur component in a petroleum refining process or a process of separating carbon dioxide from an exhaust gas discharged from a thermal power plant.

FIG. 1 shows an example of a conventional wet carbon dioxide capture facility to which a conventional wet amine process is applied.

Referring to FIG. 1, the basic structure of the wet chemical absorption process using amine includes an absorption tower 20 for contacting an exhaust gas with an amine-based absorbent, a stripping tower 30 for removing absorbed CO ₂ , , And an exhaust gas pretreatment facility. MEA (Monoethanol Amine) is a typical absorbent, and improved wet CCS absorbent can be applied to reduce renewable energy and prevent deterioration.

For example, when wet amine CCS is applied to a coal-fired power plant, the exhaust gas flowing into the CCS flows through a flue gas desulfurization (FGD) facility, a selective catalytic reduction (SCR) facility, and a dust collection facility. The content of carbon dioxide in the exhaust gas varies depending on the fuel to be burned and the operating conditions, but is usually about 15 vol.%. The exhaust gas passing through the desulfurization equipment passes through the gas-gas heat exchanger (GGH), and the exhaust gas 71 flows into the separate SOx absorption tower 10 to further remove sulfur oxides.

The exhaust gas 72 having passed through the exhaust gas pretreatment apparatus flows into the lower portion of the CO ₂ absorber 20 and the liquid absorber 81 is supplied from the upper portion of the absorber 20, The liquid-phase absorbent 81 absorbs CO ₂ , and the removal rate is about 90%. To the top of the absorption tower 20 is CO ₂ is the removed exhaust gas 73 is withdrawn, to the bottom absorber 20 is CO ₂ that has absorbed the CO ₂ - as a rich absorbent (hereinafter referred to as rich solution (rich solution) ) 82 is discharged. The absorbent absorbing CO ₂ , that is, the rich solution 82 contains CO ₂ , and its temperature is about 40 to 50 ° C. The exhaust gas from which the CO ₂ has been removed is lowered to about 40 ° C due to the water spray on the top of the absorption tower 20 and the exhaust gas 73 is again subjected to the gas- (GGH) or through separate stacks.

The rich solution 82 flows into the plate type heat exchanger 50 using the rich solution pump 21 and recover sensible heat while passing through the plate type heat exchanger 50 to be heated Rich solution 83 flows into the upper part of the demolition tower 30. [

The rich solution 83 is heated by the thermal energy as it flows downward from the top of the demolition tower 30 to be separated into the absorbent and CO ₂ and the separated CO ₂ is discharged to the top of the demolition tower 30. The temperature of the high concentration CO ₂ 91 discharged to the upper part of the stripping tower 30 is about 105 to 120 ° C. and is almost the same as the temperature of the stripping tower 30 and contains moisture corresponding to the saturated steam pressure, And the moisture thus removed flows into the deodorizing tower 30 as condensed water 92 again. The temperature of CO ₂ (93) in which moisture is removed is about 40 ° C. CO ₂ must be compressed to transport / store or reuse. To this end, the CO ₂ separated from the stripping tower 30 is removed through the condenser 60 and the reflux drum, and is connected to the compression and liquefaction processes. For compression and liquefaction, compression pressure and temperature are determined according to the conveying method. Compressed pressure and temperature are set at -20 ° C and 20 bar g for conveyance using ship or tank lorry, and 150 ° g for conveyance using piping. .

A CO ₂ -lein absorbent (hereinafter referred to as a lean solution) 84 is discharged to the lower end of the stripping tower 30. The temperature of the lean solution 84 is about 105 to 120 ° C and flows into the plate heat exchanger 50 to transfer the sensible heat to the rich solution 82. The lean solution 84 that has lost the sensible heat flows into the upper portion of the absorption tower 20 by using the lean solution pump 22 and comes into contact with the exhaust gas 71 from which the sulfur oxides are removed in the SOx absorption tower 10. [

As above, de-geotap 30 is lower in the there is lean solution 84, the CO ₂ is separated is discharged, some of absorbent 85 is re-opening 40 in the de-geotap 30 in the process in which CO ₂ is separated Lt; / RTI > A steam 94 of about 3 bar.g or more flows into the reboiler 40 and the steam 94 heats the absorbent 85 in the reheater 40. In this case, CO ₂ and steam are generated in the reheater 40 from the absorbent 85 and the mixed gas 95 flows into the stripping tower 30 to provide thermal energy for separating CO ₂ from the rich solution 83 do. The absorbent 86 from which CO ₂ has been separated from the reheater 40 flows into the deaerating tower 30 again. The steam 94 flowing into the reheater 40 conveys latent heat and is introduced and collected into the condensate tank 70 in the form of condensate 96 and then returned to the steam production process.

As described above, in the conventional wet carbon dioxide capture equipment, the sensible heat recovery structure between the absorption tower 20 and the stripping tower 30 is composed of the rich solution 82 discharged from the lower part of the absorption tower 20, When the temperature difference of the lean solution 84 discharged from the lower part of the plate-like heat exchanger 30 is large, the sensible heat exchange between the two solutions proceeds through the plate-type heat exchanger 50 to recover the heat. The recovered sensible heat increases the temperature of the rich solution 83 flowing into the demoulding tower 30, so that the heat duty of the reheater 40 required in the demounting tower 30 is reduced.

As the temperature of the rich solution 83 flowing into the stripping tower 30 after passing through the plate heat exchanger 50 is increased, the sensible heat is increased, so that the input of heat energy in the stripping tower 30 can be reduced However, when the temperature of the upper part of the demounting tower 30 becomes higher, the cooling load in the condenser 60 becomes higher. That is, the liquefaction ratio is increased. Therefore, there is a trade-off relationship between the temperature of the rich solution 83 flowing into the stripping tower 30 and the cooling load of the condenser 60, and the sensible heat is recovered from the plate heat exchanger 50 It is a structure that can not be done.

In addition, the rich solution can be separated into CO ₂ and the absorbent in the heat exchanger 50, that is, a two-phase phenomenon may occur. In this case, it is difficult to control the circulation rate of the absorbent, The ratio of the absorbent to the exhaust gas) varies, so that stable operation can not be performed. Therefore, in order to suppress the generation of the 2-phase, the rich solution must be in a liquid state until the rich solution is introduced into the stripping tower 30 through the plate heat exchanger 50, thereby limiting the recovery of the sensible heat.

As described above, the conventional wet carbon dioxide capture equipment using the wet amine CCS process has a disadvantage in that a very large amount of heat energy is required to separate CO ₂ from the absorbent in the demolition tower 30 despite the high CO ₂ removal performance .

It is an object of the present invention to provide a wet carbon dioxide capture facility having a configuration capable of reducing the energy required for separating carbon dioxide from an absorbent in a CO ₂ depleting tower .

According to an aspect of the present invention, there is provided a wet carbon dioxide capture facility including:

A CO ₂ absorption tower for reacting CO ₂ contained in the exhaust gas with an absorbent;

A CO ₂ stripping tower for separating CO ₂ from the rich solution absorbing CO ₂ from the CO ₂ absorption tower;

In the de-CO ₂ geotap reheater for supplying thermal energy to the de-CO ₂ geotap that CO ₂ is separated from the rich solution;

A first heat exchanger to heat the rich solution that has absorbed the CO ₂ in the lean solution as the CO ₂ absorber the CO ₂ is released from the CO ₂ de geotap heating the rich solution;

Mechanical compressors increase substrate (MVR) for compressing the CO ₂ gas separated by the CO ₂ de geotap; And

And a second heat exchanger for separating CO ₂ from the rich solution by heating the rich solution by exchanging CO ₂ gas compressed in the mechanical grease-supported compressor with rich solution passed through the first heat exchanger,

Wherein the rich were not CO ₂ is released from the second heat exchanger the solution is introduced into the CO ₂ de geotap it characterized in that the CO ₂ is separated.

The first heat exchanger is a plate type heat exchanger, and the second heat exchanger is a shell and tube heat exchanger. The CO ₂ gas compressed in the mechanical grease type compressor is introduced into the tube side of the second heat exchanger And the rich solution passed through the first heat exchanger may be introduced into the shell side of the second heat exchanger.

Also, steam is introduced as a heat source in the reheating, and the steam is condensed while transferring the latent heat to the CO ₂ deasphalting tower through the reheater, and the condensed water generated when the steam is condensed flows into the first condensed water tank .

In addition, the CO ₂ gas flowing into the second heat exchanger loses heat and generates condensed water. The mixed fluid in which the CO ₂ gas, the steam and the condensed water are mixed flows into the second condensed water tank, The condensed water separated from the mixed fluid can be introduced into the CO ₂ deasphalting tower.

The _apparatus may further include a third heat exchanger for exchanging CO ₂ -exhaust gas from the CO ₂ absorption tower with CO ₂ gas from which condensed water has been removed from the second condensate tank.

A second mechanical vapor compression compressor (second MVR) for compressing the CO ₂ gas from which condensed water has been removed in the second condensate water tank; A; to heat some of the passed through the first heat exchanger and the second mechanical increase compressed CO ₂ gas from the substrate compressor rich solution the fourth heat exchanger so that some CO ₂ is separated from the rich solution by heating the rich solution And the rich solution in which the CO ₂ is not separated in the fourth heat exchanger may be introduced into the CO ₂ de-coupling tower together with the rich solution in which CO ₂ can not be separated in the second heat exchanger.

Also, the fourth heat exchanger is a shell and tube heat exchanger, the CO ₂ gas compressed in the second mechanical vapor compression compressor is introduced into the tube side of the fourth heat exchanger, and the CO ₂ gas, which has passed through the first heat exchanger Some of the rich solution may be introduced into the shell side of the fourth heat exchanger.

In addition, the CO ₂ gas flowing into the fourth heat exchanger loses heat to generate condensed water, and the mixed fluid in which the CO ₂ gas, the steam and the condensed water are mixed flows into the third condensed water tank, The condensed water separated from the mixed fluid can be introduced into the CO ₂ deasphalting tower.

The _apparatus may further include a third heat exchanger for exchanging CO ₂ -exhaust gas from the CO ₂ absorption tower with CO ₂ gas from which condensed water has been removed from the third condensate tank.

The system may further include a thermal steam compressor (TVR) for compressing the re-evaporated steam generated in the first condensate tank and supplying the compressed steam to the reheater.

Also, a heat exchanger is mounted in the first condensate tank, and the heat exchanger can heat-exchange the CO ₂ gas from which the condensed water has been removed in the second condensate tank with the condensed water in the first condensate tank.

The _apparatus may further include a third heat exchanger for exchanging CO ₂ gas from the CO ₂ absorber with CO ₂ gas passed through the heat exchanger installed in the first condensate tank.

According to the present invention, since the CO ₂ is separated from the rich solution by the mechanical grease-supported compressor and the second heat exchanger, the amount of the rich solution in which the CO ₂ introduced into the upper part of the CO ₂ de- Which is reduced compared to the prior art. Therefore, it is possible to reduce the amount of heat energy supplied to the CO ₂ removal tower through the reheating, thereby reducing the heat load of reheating.

Also, in the prior art, CO ₂ is removed from the stripping tower only when it enters the compression / liquefaction process, while the pressure is 0.3 to 0.8 bar. Compared with the present invention, the CO ₂ gas, It is advantageous that the pressure during the introduction into the process is high and the load of the compression process is low.

FIG. 1 is a schematic view showing an example of a conventional wet carbon dioxide collecting facility to which a conventional wet amine process is applied.
2 is a view illustrating a wet carbon dioxide capture facility according to an embodiment of the present invention.
3 is a view illustrating a wet carbon dioxide capture facility according to another embodiment of the present invention.
4 is a view illustrating a wet carbon dioxide capture facility according to another embodiment of the present invention.

Hereinafter, embodiments of the wet carbon dioxide capture equipment according to the present invention will be described with reference to the accompanying drawings. In the drawings, the same reference numerals denote the same elements.

2 is a view illustrating a wet carbon dioxide capture facility according to an embodiment of the present invention.

2, the wet carbon dioxide capture equipment according to the present invention is a facility for separating carbon dioxide in the exhaust gas discharged from a thermal power plant or the like by a chemical absorption process, for example, a wet amine CCS process can be applied . However, the present invention is not limited to the wet amine CCS process.

The wet carbon dioxide capture facility according to one embodiment of the present invention includes a CO ₂ absorption tower 120, a CO ₂ removal tower 130, a reheater 140, a first heat exchanger 150, And a second heat exchanger (152).

For example, the exhaust gas discharged from a thermal power plant is subjected to an exhaust gas pretreatment facility, for example, a desulfurization (FGD) facility, a selective catalytic reduction (SCR) facility, and / or a dust collection facility. The content of carbon dioxide in the exhaust gas varies depending on the fuel to be burned and the operating conditions, but is usually about 15 vol.%. The exhaust gas passed through the desulfurization equipment passes through the gas-gas heat exchanger (GGH), and the exhaust gas 301 flows into the SOx absorption tower 110, and sulfur oxides can be further removed. As described above, but SOx is removed goes through the exhaust gas pre-treatment plant exhaust gas (302) containing the CO ₂ is introduced into the lower portion of the CO ₂ absorption tower 120.

The CO ₂ absorption tower 120 is a device that reacts CO ₂ in the exhaust gas with a liquid absorbent such as an amine absorbent. Specifically, there is a liquid absorbing agent 311 introduced from the top of the CO ₂ absorber 120, CO ₂ absorber 120, group the absorber 311 and the exhaust gas (302) flows in counter-current with each other in the-solution The contact proceeds and CO ₂ in the exhaust gas 302 is absorbed into the absorbent 311. At this time, the CO ₂ removal rate in the exhaust gas is about 90%.

CO ₂ has absorbed the CO ₂ as described above (hereinafter referred to as rich solution) was rich absorber 312 is discharged through the lower portion of the CO ₂ absorption tower 120. The rich solution 312 contains CO ₂ , and its temperature is about 40-50 ° C.

The exhaust gas 303 from which CO ₂ has been removed is discharged to the upper part of the CO ₂ absorption tower 120. In this process, the water spray on the CO ₂ absorption tower 20 causes the exhaust gas Lt; RTI ID = 0.0 > 40 C. < / RTI >

The rich solution 312 discharged through the lower portion of the CO ₂ absorption tower 120 flows into the first heat exchanger 150 through the rich solution pump 161. The first heat exchanger 150 may be a plate heat exchanger. The temperature of the rich solution 312 is increased while recovering sensible heat through heat exchange with a lean solution 315 which will be described later through the first heat exchanger 150. At this time, the rich solution 312 is heated to a temperature at which the two-phase phenomenon can be prevented and the liquid phase can be maintained, for example, about 90 to 100 ° C.

The heated rich solution 313 is recovered from the sensible heat and flows into the second heat exchanger 152. As the second heat exchanger 152, a shell and tube heat exchanger may be used. The rich solution 313 is heated through heat exchanging with the CO ₂ gas 322 compressed by a mechanical vapor recompression (MVR) 180 described later, through the second heat exchanger 152. This will be described later.

The second heat exchanger 152, while the rich solution 313 is heated in, and some CO ₂ is separated from the rich solution 313, the rich solution 314 that may not have CO ₂ separation is the CO ₂ de geotap (Not shown).

The CO ₂ stripping tower 130 is a device for separating CO ₂ from the rich solution 314 through heating. Specifically, the rich solution 314 is heated by the heat energy flows from the upper portion of the CO ₂ de geotap 130 to bottom are separated by the absorbent and the CO _2.

The reheater (reboiler) (140) is a device for supplying thermal energy for the CO ₂ separated from the CO ₂ de geotap 130.

More specifically, as the heat source, about 3 bar g or more of steam 351 flows into the reheater 140. Also, some of the absorbent 341 in the CO ₂ stripping tower 130 in the process of separating CO ₂ is also introduced into the reheater 140, and the steam 351 in the reheater 140 And heated. CO ₂ and water vapor are generated from the absorbent 341 in the reheater 140 and a mixed gas 342 of CO ₂ and water vapor flows into the CO ₂ stripping tower 30, from 314) to provide heat energy to remove the CO _2. The absorbent 343 from which CO ₂ has been separated from the reheater 140 flows into the CO ₂ stripping tower 130 again. The steam 351 flowing into the reheater 140 delivers latent heat and is condensed. The condensed water 352 thus generated flows into the first condensate tank 170 and is collected and returned to the steam production process.

CO ₂ separated in the CO ₂ de geotap 130 is discharged to the upper portion of the CO ₂ de geotap 130, (hereinafter referred to as lean solution) CO absorber 315, the _second has been removed is the CO ₂ de And is discharged to the lower portion of the tower 130.

The temperature of the lean solution 315 is approximately 105 to 120 ° C. As described above, the lean solution 315 flows into the first heat exchanger 150 and transfers sensible heat to the rich solution 312 through heat exchange. CO lean solution ₂ is removed and lost the sensible heat section 311, that is, the regenerated absorbent (311) is drawn by the lean solution pump 162 to the upper portion of the CO ₂ absorber 120, SOx is removed, the exhaust The gas 302 is brought into contact with the gas.

The CO ₂ de-temperature CO ₂ gas 321 is discharged to the upper portion of geotap 130 is approximately 105 ~ 120 ℃, the pressure is approximately 0.3 ~ 0.8 bar.g, water contains approximately 40%. The CO ₂ gas 321 flows into the mechanical vapor phase compressor (MVR) 180 and is compressed. At this time, the amount of moisture contained in the CO ₂ gas 321 increases as the pressure increases. The compression ratio of a conventional compressor is about 4, and the compression ratio of the mechanical expansion vessel (MVR) 180 is about 2 because the compression of the steam is performed. It can be compressed through a single-stage or multi-stage compressor. The CO ₂ gas 322 compressed by the mechanical expansion vessel compressor 180 flows into the second heat exchanger 152 at a high temperature. A shell and tube heat exchanger may be used as the second heat exchanger 152 and a compressed CO ₂ gas 322 may be introduced into the tube side of the second heat exchanger 152.

Further, as described above, the rich solution 313 heated and recovered from the first heat exchanger 150 flows into the shell side of the second heat exchanger 152. The rich solution 313 is heated in the second heat exchanger 152 through heat exchange with the compressed CO ₂ gas 322. The CO ₂ gas 322 compressed by the mechanical grease-supported compressor 180 can be heat-exchanged because the temperature of the CO ₂ gas 322 is higher than that of the rich solution 313. As a result, some CO ₂ is separated from the rich solution 313, and some water vapor is generated. A mixed gas 323 of CO ₂ gas and water vapor separated in the second heat exchanger 152 flows into the upper part of the CO ₂ removal tower 130. The rich solution 314 in which the undissolved CO ₂ has not been separated in the second heat exchanger 152 flows into the upper portion of the CO ₂ demarcation tower 130 as described above.

The compressed CO ₂ gas 322 flowing into the second heat exchanger 152 loses heat and condensed water to generate condensed water. However, since the temperature of the condensed CO ₂ gas 322 is still high, some of the CO ₂ gas exists as water vapor. The mixed fluid 324 in which the compressed CO ₂ gas, water vapor, and condensed water are mixed flows into the second condensate tank 172. The condensed water 325 separated from the mixed fluid 324 in the second condensed water tank 172 flows into the upper portion of the CO ₂ demarcation tower 130.

The compressed CO ₂ gas 326 in which the condensed water 325 is removed in the second condensed water tank 172 flows into the third heat exchanger 153. A shell and tube heat exchanger may be used as the third heat exchanger 153 and a compressed CO ₂ gas 326 may be introduced to the shell side of the third heat exchanger 153. The exhaust gas 303 from which CO ₂ has been removed from the CO ₂ absorption tower 120 flows into the tube side of the third heat exchanger 153. The temperature of the exhaust gas 30 is lowered to about 40 캜 due to cooling water spray on the CO ₂ absorption tower 120. However, this exhaust gas 303 needs to be discharged to a gas-gas heat exchanger (GGH) of a desulfurization (FGD) facility or a separate stack, so a temperature of about 95 to 100 ° C is required.

Therefore, in the third heat exchanger 153, the exhaust gas 303 is heated through heat exchange, and the compressed CO ₂ gas 326 loses its latent heat while the temperature is lowered, so that moisture in the CO ₂ gas 326 And condensed water 327 is generated. The condensed water 327 flows into the CO ₂ removal tower 130. Then, the compressed CO ₂ gas 328 in which the moisture is partially removed is connected to the compression and liquefaction process in a low temperature state. On the other hand, the exhaust gas 305 from which CO ₂ has been removed is heated by heat exchange, and the heated exhaust gas 304 is transferred to a gas-gas heat exchanger (GGH) of a desulfurization (FGD) facility or a separate stack.

As described above, in the wet carbon dioxide capture equipment according to an embodiment of the present invention, since the CO ₂ is separated from the rich solution 313 by the mechanical grease-supported compressor 180 and the second heat exchanger 152, the amount of the rich solution (314) CO ₂ has not been separated from entering the upper portion of the CO ₂ de geotap 130 is reduced compared to the prior art. Therefore, the amount of thermal energy supplied to the CO ₂ de-stacking tower 130 through the reheater 140 can be reduced, thereby further reducing the heat load of the reheater 140.

Also, when the prior to removing only water from the deionized geotap the CO ₂ in the technology and enters the compression / liquefaction process the pressure is 0.3 ~ 0.8 bar.g inde, the CO ₂ gas 328, the condensed water is removed in accordance with the invention compared The pressure during the introduction into the compression / liquefaction process is high and the load of the compression process is reduced.

3 is a view illustrating a wet carbon dioxide capture facility according to another embodiment of the present invention.

3, the wet carbon dioxide capture equipment according to another embodiment of the present invention includes a CO ₂ absorption tower 120, a CO ₂ removal tower 130, a reheater 140, a first heat exchanger 150, The second mechanical expansion device compressor 182 and the fourth heat exchanger 154 in addition to the mechanical expansion joint compressors 180 and the second heat exchanger 152. [

Some of the components of the embodiment shown in Fig. 3 are the same as those of the embodiment shown in Fig. 2, so that the description of the same components will be omitted or simplified, Will be explained mainly.

In the embodiment shown in FIG. 3, for example, the pretreatment equipment for the exhaust gas discharged from the thermal power plant is the same as the embodiment shown in FIG. 2, and a description thereof will be omitted.

The CO ₂ absorption tower 120, the CO ₂ removal tower 130, the reheater 140, the first heat exchanger 150, the mechanical expansion vessel compressor 180, and the second heat exchanger 152 2, and description thereof will be omitted.

3, since the condensed CO ₂ gas 326 in which the condensed water 325 is removed in the second condensed water tank 172 still contains moisture, (182). When the compressed CO ₂ gas 326 passes through the second mechanical compression type compressor 182, the pressure of the CO ₂ gas 326 becomes higher, so that the load of the compression equipment in the compression and liquefaction processes can be reduced.

The CO ₂ gas 329 compressed by the second mechanical vapor compression compressor 182 flows into the fourth heat exchanger 154. The fourth heat exchanger 154 may also be a shell and tube heat exchanger and the compressed CO ₂ gas 329 may be introduced into the tube side of the fourth heat exchanger 154.

3, a portion of the rich solution 313 that has obtained sensible heat through the first heat exchanger 150 flows into the shell side of the fourth heat exchanger 154, ₂ < / RTI > The fourth heat exchanger 154, the CO ₂ gas mixture (330) of the gas and the water vapor separated from the rich solution (313) through the heat exchange in the are of the CO ₂ gas and water vapor separated from the second heat exchanger (152) And then flows into the CO ₂ removal tower 130 together with the mixed gas 323.

The fourth heat exchanger the CO ₂ with 154 rich solution 316 that may not have CO ₂ is separated in the second heat exchanger 152 that may not have CO ₂ is separated in the rich solution 314 It flows into the upper portion of the DI geotap 130, inside the de-CO ₂ geotap 130 CO ₂ is separated.

The compressed CO ₂ gas 329 flowing into the fourth heat exchanger 154 loses heat and condensed water to generate condensed water. However, the temperature of the condensed CO ₂ gas 329 is still high, and some of the CO ₂ gas exists as steam. The mixed fluid 331 mixed with the compressed CO ₂ gas, water vapor and condensed water flows into the third condensate tank 173. The condensed water 332 separated from the mixed fluid 331 in the third condensed water tank 173 flows into the upper part of the CO ₂ demarcation tower 130.

The compressed CO ₂ gas 333 in which the condensed water 332 is removed in the third condensed water tank 173 flows into the shell side of the third heat exchanger 153. The operation of the third heat exchanger 153 and the subsequent contents are the same as the embodiment shown in Fig.

The wet carbon dioxide collecting facility according to another embodiment of the present invention shown in FIG. 3 has the same advantages as the embodiment shown in FIG. In particular, in the embodiment shown in FIG. 3, in addition to the mechanical expansion vessel compressor 180 and the second heat exchanger 152, the second mechanical vapor compression compressor 182 and the fourth heat exchanger 154 are further included, since separated over a part CO ₂ in the second stage from the rich solution 313, the amount of the rich solution (314, 316) is CO ₂ from entering the upper portion of the CO ₂ de geotap 130 could not be separated to be further reduced So that the amount of thermal energy supplied to the CO ₂ removal tower 130 through the reheater 140 can be further reduced.

4 is a view illustrating a wet carbon dioxide capture facility according to another embodiment of the present invention.

Referring to FIG. 4, the wet carbon dioxide capture equipment according to another embodiment of the present invention includes a CO ₂ absorption tower 120, a CO ₂ removal tower 130, a reheater 140, a first heat exchanger 150, A mechanical vapor compressor 180, a second heat exchanger 152, and a thermal vapor recompression (TVR)

Some of the components of the embodiment shown in FIG. 4 are the same as those of the embodiment shown in FIG. 2, so that the description of the same components will be omitted or simplified, Will be explained mainly.

In the embodiment shown in FIG. 4, for example, the pretreatment equipment for the exhaust gas discharged from the thermal power plant is the same as the embodiment shown in FIG. 2, and a description thereof will be omitted.

The CO ₂ absorption tower 120, the CO ₂ removal tower 130, the reheater 140, the first heat exchanger 150, the mechanical expansion vessel compressor 180, and the second heat exchanger 152 2, and description thereof will be omitted.

4, the thermal steam compressor 190 compresses the re-evaporation steam 353 generated in the first condensate tank 170 and supplies the steam to the reheater 140 do.

As described above, the steam 351 flowing into the reheater 140 is condensed while the latent heat is lost, and the condensed water 352 thus generated flows into the first condensate tank 170. Since the condensed water 352 in the first condensed water tank 170 has lost only the latent heat, the temperature of the condensed water 352 is 140 ° C or higher. Therefore, when the thermal storage medium compressor 190 is connected to the first condensed water tank 170 The flash steam 353 is generated from the condensed water 352 while the first condensed water tank 170 is depressurized. Thus, when the re-evaporation steam 353 is generated, the temperature of the condensed water 352 becomes about 100 ° C. The steam evaporator 353 can be compressed by the thermal steam compressor 190 and supplied to the reheater 140 so that the amount of the steam 351 supplied to the reheater 140 can be reduced There are advantages.

4, before the compressed CO ₂ gas 326 in which the condensed water 325 is removed in the second condensed water tank 172 flows into the third heat exchanger 153, Can be introduced into a separate heat exchanger (175) mounted in the first condensate tank (170).

Since the compressed CO ₂ gas 326 is in a high temperature state, heat can be supplied to the condensed water 352 through heat exchange while passing through a heat exchanger 175 mounted in the first condensed water tank 170. Accordingly, since the amount of the re-evaporation steam 353 generated from the condensed water 352 is further increased, the amount of the steam 351 supplied to the reheat 140 can be further reduced.

The compressed CO ₂ gas 326 flows into the shell side of the third heat exchanger 153 after passing through the heat exchanger 175 mounted on the first condensate tank 170. The operation of the third heat exchanger 153 and the subsequent contents are the same as the embodiment shown in Fig.

The wet carbon dioxide collecting facility according to another embodiment of the present invention shown in FIG. 4 has the same advantages as the embodiment shown in FIG. In particular, in the embodiment shown in FIG. 4, the system further includes the thermal steam compressor 190, and a high temperature compressed CO ₂ gas 326 is supplied to a heat exchanger 175 (not shown) mounted in the first condensate tank 170 The amount of the steam 351 supplied to the reheater 140 can be reduced by exchanging heat with the condensed water 352 through the reheater 140 to generate the reboiler 353, ₂ has the advantage of further reducing the amount of thermal energy supplied to the de-geotap 130.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art. There will be. Accordingly, the true scope of protection of the present invention should be determined by the appended claims.

110 ... SOx absorber 120 ... CO ₂ absorption tower
130 ... CO ₂ removal tower 140 ... re-opening
150 ... first heat exchanger 152 ... second heat exchanger
153 ... third heat exchanger 154 ... fourth heat exchanger
161 ... rich solution pump 162 ... lean solution pump
170 ... first condensate tank 172 ... second condensate tank
173 ... third condensate tank 175 ... heat exchanger
180 ... mechanical expansion vessel compressor 182 ... second mechanical expansion vessel compressor
190 ... thermal grease compressor

Claims (12)

A CO ₂ absorption tower for reacting CO ₂ contained in the exhaust gas with an absorbent;
A CO ₂ stripping tower for separating CO ₂ from the rich solution absorbing CO ₂ from the CO ₂ absorption tower;
In the de-CO ₂ geotap reheater for supplying thermal energy to the de-CO ₂ geotap that CO ₂ is separated from the rich solution;
A first heat exchanger to heat the rich solution that has absorbed the CO ₂ in the lean solution as the CO ₂ absorber the CO ₂ is released from the CO ₂ de geotap heating the rich solution;
Mechanical compressors increase substrate (MVR) for compressing the CO ₂ gas separated by the CO ₂ de geotap; And
And a second heat exchanger for separating CO ₂ from the rich solution by heating the rich solution by exchanging CO ₂ gas compressed in the mechanical grease-supported compressor with rich solution passed through the first heat exchanger,
Rich solution could not be CO ₂ is released from the second heat exchanger is wet carbon capture facility, characterized in that the CO ₂ is introduced into the CO ₂ separation deionized geotap. The method according to claim 1,
Wherein the first heat exchanger is a plate type heat exchanger and the second heat exchanger is a shell and tube heat exchanger, the CO ₂ gas compressed in the mechanical grease type compressor flows into the tube side of the second heat exchanger, And the rich solution passing through the first heat exchanger flows into the shell side of the second heat exchanger. The method according to claim 1,
The steam is introduced into the first condensate water tank through the reheater, while the steam is condensed while transferring the latent heat to the CO ₂ deasphalting tower. The condensed water generated by condensing the steam is introduced into the first condensate water tank Wet carbon dioxide capture facility. The method of claim 3,
Wherein the CO ₂ gas flowing into the second heat exchanger loses heat and generates condensed water. The mixed fluid in which the CO ₂ gas, the steam and the condensed water are mixed flows into the second condensed water tank, and in the second condensed water tank, And the condensed water separated from the mixed fluid flows into the CO ₂ demarcation tower. 5. The method of claim 4,
Further comprising a third heat exchanger for exchanging CO ₂ -exhaust gas from the CO ₂ absorption tower with CO ₂ gas from which condensed water has been removed from the second condensate tank. 5. The method of claim 4,
A second mechanical vapor compressor (second MVR) for compressing CO ₂ gas from which condensed water has been removed in the second condensate tank;
A; to heat some of the passed through the first heat exchanger and the second mechanical increase compressed CO ₂ gas from the substrate compressor rich solution the fourth heat exchanger so that some CO ₂ is separated from the rich solution by heating the rich solution Further,
Wherein the rich solution in which the CO ₂ is not separated in the fourth heat exchanger flows into the CO ₂ de-coupling tower together with the rich solution in which the CO ₂ is not separated in the second heat exchanger. The method according to claim 6,
Wherein the fourth heat exchanger is a shell and tube heat exchanger, the CO ₂ gas compressed in the second mechanical vapor compression compressor flows into the tube side of the fourth heat exchanger, and the rich solution passing through the first heat exchanger Of the second heat exchanger is introduced into the shell side of the fourth heat exchanger. The method according to claim 6,
The condensed water is generated when the CO ₂ gas flowing into the fourth heat exchanger loses heat and the mixed fluid in which the CO ₂ gas, the steam and the condensed water are mixed flows into the third condensed water tank, and in the third condensed water tank, And the condensed water separated from the mixed fluid flows into the CO ₂ demarcation tower. 9. The method of claim 8,
Further comprising a third heat exchanger for exchanging CO ₂ -exhaust gas from the CO ₂ absorption tower with CO ₂ gas from which condensed water has been removed from the third condensate tank. 5. The method of claim 4,
Further comprising a thermoregulated gas compressor (TVR) for compressing the re-evaporated steam generated in the first condensed water tank and supplying the re-evaporated steam to the reheater. 11. The method of claim 10,
A heat exchanger is mounted in the first condensate tank and the heat exchanger exchanges CO ₂ gas with condensed water in the second condensate tank with condensate in the first condensate tank. 12. The method of claim 11,
Further comprising a third heat exchanger for exchanging CO ₂ gas through the heat exchanger installed in the first condensate tank and the exhaust gas from which CO ₂ has been removed from the CO ₂ absorption tower.

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